ObjectiveC Generics: Start using ObjCTypeParamType.

For ObjC type parameter, we used to have TypedefType that is canonicalized to
id or the bound type. We can't represent "T <protocol>" and thus will lose
the type information in the following example:
@interface MyMutableDictionary<KeyType, ObjectType> : NSObject
- (void)setObject:(ObjectType)obj forKeyedSubscript:(KeyType <NSCopying>)key;
@end
MyMutableDictionary<NSString *, NSString *> *stringsByString;
NSNumber *n1, *n2;
stringsByString[n1] = n2;
--> no warning on type mismatch of the key.

To fix the problem, we introduce a new type ObjCTypeParamType that supports
a list of protocol qualifiers.

We create ObjCTypeParamType for ObjCTypeParamDecl when we create
ObjCTypeParamDecl. We also substitute ObjCTypeParamType instead of TypedefType
on an ObjCTypeParamDecl.

rdar://24619481
rdar://25060179

Differential Revision: http://reviews.llvm.org/D23080

llvm-svn: 281358

2 files changed, 42 insertions, 1 deletions

diff --git a/clang/test/SemaObjC/kindof.m b/clang/test/SemaObjC/kindof.m
index 63ba18fe89b..9d758d3cfb2 100644
--- a/clang/test/SemaObjC/kindof.m
+++ b/clang/test/SemaObjC/kindof.m
@@ -385,7 +385,7 @@ void testNullability() {
 @end
 
 @interface NSGeneric<ObjectType> : NSObject
-- (void)test:(__kindof ObjectType)T;
+- (void)test:(__kindof ObjectType)T; // expected-note{{passing argument to parameter 'T' here}}
 - (void)mapUsingBlock:(id (^)(__kindof ObjectType))block;
 @end
 @implementation NSGeneric
@@ -395,6 +395,14 @@ void testNullability() {
 }
 @end
 
+void testGeneric(NSGeneric<NSString*> *generic) {
+  NSObject *NSObject_obj;
+  // Assign from NSObject_obj to __kindof NSString*.
+  [generic test:NSObject_obj]; // expected-warning{{incompatible pointer types sending 'NSObject *' to parameter of type '__kindof NSString *'}}
+  NSString *NSString_str;
+  [generic test:NSString_str];
+}
+
 // Check that clang doesn't crash when a type parameter is illegal.
 @interface Array1<T> : NSObject
 @end
diff --git a/clang/test/SemaObjC/parameterized_classes_subst.m b/clang/test/SemaObjC/parameterized_classes_subst.m
index f90ee909359..da2d56f11bc 100644
--- a/clang/test/SemaObjC/parameterized_classes_subst.m
+++ b/clang/test/SemaObjC/parameterized_classes_subst.m
@@ -426,3 +426,36 @@ void test_ternary_operator(NSArray<NSString *> *stringArray,
 // warning about likely protocol/class name typos.
 // --------------------------------------------------------------------------
 typedef NSArray<NSObject> ArrayOfNSObjectWarning; // expected-warning{{parameterized class 'NSArray' already conforms to the protocols listed; did you forget a '*'?}}
+
+// rdar://25060179
+@interface MyMutableDictionary<KeyType, ObjectType> : NSObject
+- (void)setObject:(ObjectType)obj forKeyedSubscript:(KeyType <NSCopying>)key; // expected-note{{passing argument to parameter 'obj' here}} \
+    // expected-note{{passing argument to parameter 'key' here}}
+@end
+
+void bar(MyMutableDictionary<NSString *, NSString *> *stringsByString,
+                             NSNumber *n1, NSNumber *n2) {
+  // We warn here when the key types do not match.
+  stringsByString[n1] = n2; // expected-warning{{incompatible pointer types sending 'NSNumber *' to parameter of type 'NSString *'}} \
+    // expected-warning{{incompatible pointer types sending 'NSNumber *' to parameter of type 'NSString<NSCopying> *'}}
+}
+
+@interface MyTest<K, V> : NSObject <NSCopying>
+- (V)test:(K)key;
+- (V)test2:(K)key; // expected-note{{previous definition is here}}
+- (void)mapUsingBlock:(id (^)(V))block;
+- (void)mapUsingBlock2:(id (^)(V))block; // expected-note{{previous definition is here}}
+@end
+
+@implementation MyTest
+- (id)test:(id)key {
+  return key;
+}
+- (int)test2:(id)key{ // expected-warning{{conflicting return type in implementation}}
+  return 0;
+}
+- (void)mapUsingBlock:(id (^)(id))block {
+}
+- (void)mapUsingBlock2:(id)block { // expected-warning{{conflicting parameter types in implementation}}
+}
+@end